Nowadays, a DVD (Digital Versatile Disc) is often used as a medium on which data such as audio and video is recorded. In the DVD, data is divided to a plurality of groups (or titles) to be recorded. In each group, a plurality of tracks (or chapters) is provided. The contents such as audio and video in each group are divided to a plurality of tracks in the group to be recorded.
Further, in a DVD-Audio or the like, the audio is allowed to be recorded multi-channel other than conventional two-channel, and allowed to be reproduced with a higher sound quality and a higher realistic sensation (for example, see Patent Document 1).
[Patent Document 1] Japanese Published Patent Application No. 2004-103207